• Journal of Convergence for Information Technology
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• v.11 no.9
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• pp.124-129
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• 2021

A time-interpolation technique has been applied to the conventional FLASH analog-to-digital converter (ADC) to increase a number of quantization level, thus it reduces not only a power dissipation, but also minimize an active chip area. In this work, we demonstrated 5-bit ADC which has 31 quantization levels consisting of 16 conventional voltage-mode comparators and 15 time-mode comparators. As a result, we have achieved about 48.4% voltage-mode comparator reductions. The ADC is fabricated in a 14nm fin Field-effect transistor (FinFET) process with an active die area of 0.0024 mm2 while consuming 0.82 mW through a 0.8 V supply. At 400-MS/s conversion rate, the ADC performs 28.03 dB SNDR (4.36 ENOB) at 21MHz input frequency.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.317-321
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• 1991

In recent years, the discrete-data and digital control systems have gained importance in all industies due in part to the advances made in microcomputers, as well as the advantages found in working with digital signals. So, the developments of the computer aided design packages to analysis, control law design and digital implementation of control systems are increasingly needed and those substantial technological improvements are now expected. In the paper, a real time control program package(RTCPP) for the implementation of digital control is developed by using C language. The digital controls for the feedfoward and feedback controllers such as PI(propotional and Integration) type, regulator and servo types can be implemented by an IBM PC compatible computer with some interface modules of A-D/D-A converter and RS-232C. The effectiveness of RTCPP is illustrated by the application controls for motor and magnetic levitation systems.

• Korean Journal of Remote Sensing
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• v.30 no.2
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• pp.251-258
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• 2014

We upgraded to utilize a novel method for combining the analog to digital converter and photon-counting measurements for backscatter photon signal of lidar. We have and improve the standard combining method for determination of those conversion factors between analog to digital converter data and photon-counting data measurement which is conducted dead time correction. The combining method and dead time correction method presented here has been successfully applied to experimental data obtained in Gwangju, Korea.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.2
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• pp.162-168
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• 2005

In this paper, a digital current mode control is designed for the power converter applications. The designed digital current mode controller is derived analytically from the continuous time small signal model of the power converters. Due to the small signal model based derivations of the control law, the designed control method can be applicable to boost, buck, and buck-boost converters. It is also proven that the controlled power converter employing the designed digital current mode controller is always stable regardless of an operating conditions. In order to show the usefulness of a designed controller, experiments are carried out using a 16bit DSP micro-processor, TMS320LF2406A.

• The Journal of Information Technology
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• v.4 no.4
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• pp.51-63
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• 2001

Residue Number System has carry free operation and parallelism each modulus, So it is used for special purpose processor such as Digital Signal Processing and Neuron Processor. Magnitude comparison and sign detection are in need of Mixed Radix Conversion, and these operations are impediment to improve the operation speed. So in this Paper, MRC(Mixed Radix Converter) is designed using modified partitioned residue to speed up the operation of MRC, so it has progressed maximum twice operation time but increased the size of converter comparison to other converter.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.3
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• pp.186-190
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• 2005

In this paper, the pipelined A/D converter with multi S/H stage structure is proposed for high resolution and high-speed data conversion rate. In order to improve a resolution and operational speed, the proposed structure increased the sampling time that is sampled input signal. In order to verify the operation characteristics, 20MS/s pipelined A/D converter is designed with two S/H stage. The simulation result shows that INL and DNL are $0.52LSB\~-0.63LSB$ and $0.53LSB\~-0.56LSB$, respectively. Also, the designed Analog-to-Digital converter has the SNR of 43dB and power consumption is 18.5mW.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.327-331
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• 2008

The problems of power factor and harmonics are occurred in converter system which used to SCRs and diodes as power semiconductor devices IGBT was solved that problem, maintain the input line current with sinusoidal wave current of input power source voltage. In this paper, three phase AC to DC boost converter that operates with unity power factor and sinusoidal input currents is presented. The current control of the converter is based on the space vector PWM strategy with fixed switching frequency and the input current tracks the reference current within one sampling time interval. Space vector PWM strategy for current control was materialized as a digital control method. By using this control strategy low ripples in the output voltage, low harmonics in the input current and fast dynamic responses are achieved with a small capacitance in the dc link.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.2
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• pp.378-384
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• 2013

In this paper, a CMOS temperature sensor is proposed to measure the internal temperature of a chip. The temperature sensor consists of a proportional-to-absolute-temperature (PTAT) circuit for a temperature sensing part and a 4-bit analog-to-digital converter (ADC) for a digital interface. The PTAT circuit with the compact area is designed by using a vertical PNP architecture in the CMOS process. To reduce sensitivity of temperature variation in the digital interface circuit of the proposed temperature sensor, a 4-bit successive approximation (SA) ADC using the minimum analog circuits is used. It uses a capacitor-based digital-to-analog converter and a time-domain comparator to minimize power consumption. The proposed temperature sensor was fabricated by using a $0.25{\mu}m$ 1-poly 6-metal CMOS process with a 2.5V supply, and its operating temperature range is from 50 to $150^{\circ}C$. The area and power consumption of the fabricated temperature sensor are $130{\times}390{\mu}m^2$ and $868{\mu}W$, respectively.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.2
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• pp.25-32
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• 2004

Purpose : The simulator is used to determine patient field and ensure the treatment field, which encompasses the required anatomy during patient normal movement such as during breathing. The latest simulator provide real time display of still, flouroscopic and digitalized image, but conventional simulator is not yet. The purpose of this study is to introduce digital image capture system(DICS) using conventional simulator and clinical case using digital captured still and flouroscopic image. Methods and materials : We connect the video signal cable to the video terminal in the back up of simulator monitor, and connect the video jack to the A/D converter. After connection between the converter jack and computer, We can acquire still image and record flouroscopic image with operating image capture program. The data created with this system can be used in patient treatment, and modified for verification by using image processing software. (j.e. photoshop, paintshop) Result : DICS was able to establish easy and economical procedure. DCIS image was helpful for simulation. DICS imaging was powerful tool in the evaluation of the department specific patient positioning. Conclusion : Because the commercialized simulator based of digital capture is very expensive, it is not easily to establish DICS simulator in the most hospital. DICS using conventional simulator enable to utilize the practical use of image equal to high cost digitalized simulator and to research many clinical cases in case of using other software program.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.282-287
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• 1987

This paper presents the development of a microcomputer-aided design program for a digital control system. The program has been written in GWBASIC language which is suitable for Intel 8086II CPU with 640KB memory. By utilizing this program, sampling time, the number of bits A/D and D/A converter, and the stability for the digital control system carl be determined, To demonstrate the utility of this program, a microcomputer controlled precision temperature control system has been employed as an example.